<?php
-
/**
- * @file src/Util/HTTPSignature.php
+ * @copyright Copyright (C) 2020, Friendica
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
*/
+
namespace Friendica\Util;
use Friendica\Database\DBA;
}
/**
- * @brief
- *
* @param array $head
* @param string $prvkey
* @param string $keyid (optional, default 'Key')
}
/**
- * @brief
- *
* @param array $head
* @param string $prvkey
* @param string $alg (optional) default 'sha256'
}
/**
- * @brief
- *
* @param string $header
- * @return array associate array with
+ * @return array associative array with
* - \e string \b keyID
+ * - \e string \b created
+ * - \e string \b expires
* - \e string \b algorithm
* - \e array \b headers
* - \e string \b signature
*/
public static function parseSigheader($header)
{
- $ret = [];
- $matches = [];
+ // Remove obsolete folds
+ $header = preg_replace('/\n\s+/', ' ', $header);
- // if the header is encrypted, decrypt with (default) site private key and continue
- if (preg_match('/iv="(.*?)"/ism', $header, $matches)) {
- $header = self::decryptSigheader($header);
- }
+ $token = "[!#$%&'*+.^_`|~0-9A-Za-z-]";
- if (preg_match('/keyId="(.*?)"/ism', $header, $matches)) {
- $ret['keyId'] = $matches[1];
- }
+ $quotedString = '"(?:\\\\.|[^"\\\\])*"';
- if (preg_match('/algorithm="(.*?)"/ism', $header, $matches)) {
- $ret['algorithm'] = $matches[1];
- } else {
- $ret['algorithm'] = 'rsa-sha256';
- }
+ $regex = "/($token+)=($quotedString|$token+)/ism";
- if (preg_match('/headers="(.*?)"/ism', $header, $matches)) {
- $ret['headers'] = explode(' ', $matches[1]);
- }
+ $matches = [];
+ preg_match_all($regex, $header, $matches, PREG_SET_ORDER);
- if (preg_match('/signature="(.*?)"/ism', $header, $matches)) {
- $ret['signature'] = base64_decode(preg_replace('/\s+/', '', $matches[1]));
+ $headers = [];
+ foreach ($matches as $match) {
+ $headers[$match[1]] = trim($match[2] ?: $match[3], '"');
}
- if (!empty($ret['signature']) && !empty($ret['algorithm']) && empty($ret['headers'])) {
- $ret['headers'] = ['date'];
+ // if the header is encrypted, decrypt with (default) site private key and continue
+ if (!empty($headers['iv'])) {
+ $header = self::decryptSigheader($headers, DI::config()->get('system', 'prvkey'));
+ return self::parseSigheader($header);
+ }
+
+ $return = [
+ 'keyId' => $headers['keyId'] ?? '',
+ 'algorithm' => $headers['algorithm'] ?? 'rsa-sha256',
+ 'created' => $headers['created'] ?? null,
+ 'expires' => $headers['expires'] ?? null,
+ 'headers' => explode(' ', $headers['headers'] ?? ''),
+ 'signature' => base64_decode(preg_replace('/\s+/', '', $headers['signature'] ?? '')),
+ ];
+
+ if (!empty($return['signature']) && !empty($return['algorithm']) && empty($return['headers'])) {
+ $return['headers'] = ['date'];
}
- return $ret;
+ return $return;
}
/**
- * @brief
- *
- * @param string $header
- * @param string $prvkey (optional), if not set use site private key
- *
- * @return array|string associative array, empty string if failue
- * - \e string \b iv
- * - \e string \b key
- * - \e string \b alg
- * - \e string \b data
+ * @param array $headers Signature headers
+ * @param string $prvkey The site private key
+ * @return string Decrypted signature string
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
- private static function decryptSigheader($header, $prvkey = null)
+ private static function decryptSigheader(array $headers, string $prvkey)
{
- $iv = $key = $alg = $data = null;
-
- if (!$prvkey) {
- $prvkey = DI::config()->get('system', 'prvkey');
- }
-
- $matches = [];
-
- if (preg_match('/iv="(.*?)"/ism', $header, $matches)) {
- $iv = $matches[1];
- }
-
- if (preg_match('/key="(.*?)"/ism', $header, $matches)) {
- $key = $matches[1];
- }
-
- if (preg_match('/alg="(.*?)"/ism', $header, $matches)) {
- $alg = $matches[1];
- }
-
- if (preg_match('/data="(.*?)"/ism', $header, $matches)) {
- $data = $matches[1];
- }
-
- if ($iv && $key && $alg && $data) {
- return Crypto::unencapsulate(['iv' => $iv, 'key' => $key, 'alg' => $alg, 'data' => $data], $prvkey);
+ if (!empty($headers['iv']) && !empty($headers['key']) && !empty($headers['data'])) {
+ return Crypto::unencapsulate($headers, $prvkey);
}
return '';
$algorithm = null;
+ // Wildcard value where signing algorithm should be derived from keyId
+ // @see https://tools.ietf.org/html/draft-ietf-httpbis-message-signatures-00#section-4.1
+ // Defaulting to SHA256 as it seems to be the prevalent implementation
+ // @see https://arewehs2019yet.vpzom.click
+ if ($sig_block['algorithm'] === 'hs2019') {
+ $algorithm = 'sha256';
+ }
+
if ($sig_block['algorithm'] === 'rsa-sha256') {
$algorithm = 'sha256';
}